1. Field of the Invention
The present invention relates to a living body tissue harvesting apparatus for pulling and harvesting living body tissues such as a subcutaneous vessel under endoscopic observation.
2. Description of the Related Art
In a bypass surgery of a blood vessel of heart in recent years, a vessel of a lower limb of a patient that is his/her own great saphenous vein or the like is occasionally used. A living body tissue harvesting apparatus for harvesting such vessel of the lower limb under endoscopic observation has been proposed, for example, in Japanese Unexamined Patent Application Publication No. 2004-008241.
Such living body tissue harvesting apparatus is composed of instruments such as a dissector, harvester, or the like. Through the dissector and harvester, an endoscope can be inserted, and an operator can harvest a blood vessel while watching the endoscopic image.
The dissector is an instrument which is inserted from a trocar that is a guide tube set to an incision part in the vicinity below a patient's knee, and by being inserted through the entire length of the blood vessel to be harvested, which gradually dissects the blood vessel and the peripheral tissues. The harvester is an instrument having a bipolar cutter for electrically cutting a side branch of the vessel dissected from the peripheral tissues by the dissector.
In the bipolar cutter of the harvester disclosed in Japanese Unexamined Patent Application Publication No. 2004-008241, a groove is provided at the tip portion thereof and a set of electrodes are arranged above and below the groove respectively. A side branch, which has gotten into the groove at the tip portion, may be cut due to the discharge that occurs between the two electrodes of the set while the blood stanching is ensured. In the bipolar cutter, the cutter body is formed of a synthetic resin such as polycarbonate that is a transparent member or ceramics.